The proposed research analyzes processes underlying changes in infant visual attention as a function of experience with a stimulus. Previous research has established that at least two separate processes interact to determine the attentional reaction: A memorial process (habituation) controlling response decrements, and an arousal process (sensitization) controlling transient response increments. Furthermore, a link has been established betweeen the sensitization process and the suprathreshold contrast of the pattern. Four avenues of research are proposed to extend this analysis. The first focuses on the generality of the sensitization process by testing (a) whether a sensitizing visual stimulus will enhance attention to any other visual stimulus, and (b) whether auditory stimulation can energize visual attention. The second line of research involves further use of the linear systems analysis to study the stimulus determinants of the sensitization process. The "fit" between infants' visual capabilities and the pattern's stimulus energy appears to be the crucial variable; this analysis offers a powerful approach to ontogenetic changes in visual attention. The third research area includes several applications of the dual process analysis outside its initial testing ground. In particular, studies on (a) novelty versus familiarity preferences, and (b) differences between pre- and full-term infants' attentional responses are proposed. The main hypothesis tested here is that sensitization differences contribute to both phenomena. Finally, the consequences of sensitization for learning and memory are considered. Sensitization prolongs visual fixation and may, therfore, improve encoding. The dual-process analysis of infant visual attention suggests that changes in attention as a function of experience reflect not only cognitive factors, but also sensory-perceptual and motivational factors. These multiple determining factors lead to re-interpretations of some existing data, and have implications for clinical and practical applications of infant attention paradigms.